One of the most striking developments in recent biology has been the proliferation of concepts such as coding, information, representation and programming, especially applied to genes. The idea that genes can be described as having semantic properties, as well as ordinary causal properties, has become so uncontroversial in many quarters that it now appears prominently in biology textbooks. Scott Gilbert's widely used developmental biology text, to pick just one example, tell us that "the inherited information needed for development and metabolism is encoded in the DNA sequences of the chromosomes" (Gilbert 1997 p. 5).